[Successful management of acquired factor V deficiency developing shortly after induction of hemodialysis]

Autoimmune factor V deficiency (AiF5D) is caused by autoantibodies to coagulation factor V (FV); its clinical manifestations range from asymptomatic to fatal hemorrhage. Herein, we report the case of a 68-year-old man who was diagnosed with end-stage renal disease at the time of a femoral fracture and developed AiF5D after initiating hemodialysis. A wound infection that occurred after joint replacement was treated with antibiotics; however, it was poorly controlled. One month after the procedure, his coagulation time prolonged. The infection was improved by debridement and antibiotics; however, the coagulation time was not decreased and poor hemostasis at the shunt was still persistent. Because ELISA detected anti-FV-binding IgG with FV activity of <2.8% and FV inhibitor levels were 11.8 BU/ml, AiF5D was diagnosed. Oral prednisolone (PSL) was started. Dialysis was initially performed without anticoagulants, but blood clots were not found in the circuit. Anticoagulants were resumed when the coagulation time decreased. After achieving complete remission, PSL dose was tapered and finally discontinued. Few reports have described the management of AiF5D via dialysis. We consider that our report would be useful for the management of patients with similar manifestations.

[Recurrence of acquired factor V inhibitor after four years of remission]

Acquired factor V inhibitor (AFV-I) is a rare bleeding disorder wherein autoantibodies are developed against coagulation factor V (FV). The clinical symptoms are variable, from laboratory abnormalities without bleeding to life-threatening hemorrhage. We report herein the case of a patient with AFV-I with two relapses 4 years after the first remission. A 66-year-old male was diagnosed with AFV-I in March 20XX-4. He was treated with prednisolone (PSL) at 50 mg/day and achieved remission within 1 month. PSL dose was tapered to oral administration of 2.5 mg every other day, and long-term remission was maintained. He had been treated with dual antiplatelet therapy (DAPT) for old myocardial infarction. FV activity was markedly reduced to 3.4%, and FV inhibitor was detected (1.0 BU/ml) in May 20XX. We followed the patient without increasing the treatment dose for 2 months, but no spontaneous improvement was seen. Because DAPT was ongoing, we judged that the bleeding risk was high, although only minor bleeding symptoms appeared. PSL was therefore increased to 40 mg/day in June. FV inhibitor rapidly disappeared. When PSL dose was gradually decreased, FV activity decreased, and subcutaneous bleeding occurred in February 20XX＋1. PSL dose was increased again for the second relapse, and the patient achieved remission. Few reports have described recurrent AFV-I, and no cases of two relapses have been reported. We believe that this case report is useful for examining the long-term management of AFV-I.